/*
 * Copyright (C) 2016 Jared Boone, ShareBrained Technology, Inc.
 *
 * This file is part of PortaPack.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef __CPLD_XILINX_H__
#define __CPLD_XILINX_H__

#include "jtag_tap.hpp"

#include "utility.hpp"

#include <cstdint>
#include <cstddef>
#include <array>

namespace cpld {
namespace xilinx {

using jtag::tap::state_t;

class XC2C64A {
   public:
    using block_id_t = uint8_t;

    static constexpr size_t block_length = 274;
    static constexpr size_t blocks_count = 98;

    static constexpr size_t block_bytes = (block_length + 7) >> 3;

    struct verify_block_t {
        block_id_t id;
        std::array<uint8_t, block_bytes> data;
        std::array<uint8_t, block_bytes> mask;
    };

    struct program_block_t {
        block_id_t id;
        std::array<uint8_t, block_bytes> data;
    };

    using verify_blocks_t = std::array<verify_block_t, blocks_count>;

    constexpr XC2C64A(
        jtag::Target& jtag_interface)
        : tap{jtag_interface} {
    }

    void write_sram(const verify_blocks_t& blocks);
    bool verify_sram(const verify_blocks_t& blocks);

    bool verify_eeprom(const verify_blocks_t& blocks);
    void init_from_eeprom();

    void prepare_read_eeprom();
    void prepare_read_sram();
    std::array<bool, block_length> read_block_eeprom(block_id_t id);
    std::array<bool, block_length> read_block_sram(verify_block_t block);
    void finalize_read_eeprom();
    void finalize_read_sram(block_id_t id);

   private:
    static constexpr size_t idcode_length = 32;
    using idcode_t = uint32_t;

    static constexpr size_t ir_length = 8;
    static constexpr size_t block_id_length = 7;

    static constexpr idcode_t idcode = 0x06e58093;
    static constexpr idcode_t idcode_mask = 0x0fff8fff;

    using ir_t = uint8_t;

    jtag::tap::TAPMachine tap;

    enum class instruction_t : ir_t {
        INTEST = 0b00000010,            // -> boundary-scan
        BYPASS = 0b11111111,            // -> bypass
        SAMPLE = 0b00000011,            // -> boundary-scan
        EXTEST = 0b00000000,            // -> boundary-scan
        IDCODE = 0b00000001,            // -> device ID
        USERCODE = 0b11111101,          // -> device ID
        HIGHZ = 0b11111100,             // -> bypass
        ISC_ENABLE_CLAMP = 0b11101001,  // -> ISC shift
        ISC_ENABLE_OTF = 0b11100100,    // -> ISC shift
        ISC_ENABLE = 0b11101000,        // -> ISC shift
        ISC_SRAM_READ = 0b11100111,     // -> ISC shift
        ISC_WRITE = 0b11100110,         // -> ISC shift, alias ISC_SRAM_WRITE
        ISC_ERASE = 0b11101101,         // -> ISC shift
        ISC_PROGRAM = 0b11101010,       // -> ISC shift
        ISC_READ = 0b11101110,          // -> ISC shift, alias ISC_VERIFY
        ISC_INIT = 0b11110000,          // -> ISC shift
        ISC_DISABLE = 0b11000000,       // -> ISC shift
        TEST_ENABLE = 0b00010001,       // alias Private1
        BULKPROG = 0b00010010,          // alias Private2
        ERASE_ALL = 0b00010100,         // alias Private4
        MVERIFY = 0b00010011,           // alias Private3
        TEST_DISABLE = 0b00010101,      // alias Private5
        ISC_NOOP = 0b11100000,          // -> bypass
    };

    bool shift_ir(const instruction_t instruction);

    void reset();
    void enable();
    void enable_otf();
    void discharge();
    void init();
    void disable();
    bool bypass();
};

} /* namespace xilinx */
} /* namespace cpld */

#endif /*__CPLD_XILINX_H__*/
